1. Field of the Invention
The invention is related to the art of toothbrushes.
2. Description of Related Art
The invention relates more particularly to electrically driven toothbrushes in which brush bristles are arranged to be moved relative to the toothbrush handle. There are many examples of such toothbrushes including the disclosure in 1939 of rotary driven bristles in U.S. Pat. No. 2,215,031, A similar rotational drive arrangement is also shown in U.S. Pat. Nos. 4,845,795, 4,156,620 explains how a rotational motor drive is converted into reciprocal linear motion to drive the bristles rotationally clockwise and counterclockwise, U.S. Pat. No. 3,577,579 discloses a toothbrush in which a toothbrush head is moved in relation to a brush holder so that all the bristles mounted in the brush head move together sideways and backwards and forwards relative to the holder. U.S. Pat. No. 5,625,916, the substance of which is hereby incorporated by reference, discloses a toothbrush with a single bristle holder. The bristle holder is driven to vibrate in a rotational manner about a shaft.
The drive mechanisms and brush motions disclosed in these references range from the relatively simple to the relatively complex. The most complex of the disclosed toothbrushes is used to provide an elaborate brushing motion. While the provided brushing motion is beneficial, the means disclosed for providing it is far too complicated and involves far too many moving parts, to be a practical brushing solution in many applications. The simpler of the disclosed toothbrushes, provide only one brushing action. While practical to produce, these single brushing actions may be inadequate in some brushing applications. For example, they may not adequately clean spaces between teeth.
It is desirable therefore, to provide a toothbrush that is simple to manufacture, and has few moving parts, while providing a plurality of cleaning or brushing actions for accomplishing a plurality of teeth cleaning tasks.